The maternal, perinatal and neonatal morbidity and mortality rates for Brazil are five to ten-fold higher that that reported for developed countries. In Sao Paulo for the year 1998, 127 matemal deaths were recorded. The maternal death rate was 57 per 100,000 live births. Twenty-four of these deaths were directly attributable to complications of eclampsia and preeclampsia. An additional four deaths were related to chronic hypertension. Overall hypertensive complications of pregnancy were associated with 28 maternal deaths and ranked as the number one cause of maternal death (22%). As high as the Sao Paulo maternal mortality rate was, in Brazil for the same year the rate was 140 per 100,000. Complications of hypertensive disease were the most common cause of death (28.5%). The infrastructure and monies to train health professionals in the techniques of clinical research is inadequate in Brazil. As a result, outcomes-based research that might identify methods to eliminate the causes of morbidity and mortality that are specific to Brazil are not performed, or when performed, are likely to be flawed in one way or another, so that accurate conclusions cannot be made. By providing mentored experience in all phases of clinical research to Brazilian health professionals, well designed outcome-based research can be accomplished that will direct changes in clinical management and public policy that will reduce maternal and perinatal morbidity and mortality rates. The aims of this proposal are to: 1) study the efficacy of antioxidant therapy initiated at or before 20 weeks of gestation to reduce the incidence and severity of preeclampsia in a high risk obstetric population in Sao Paulo Brazil; 2) integrate this research effort with the training of a Brazilian scientist (concurrent application to the International Women?s and Children?s Health Research Training Grant TW-00-007); and 3) stimulate and facilitate international collaborative women?s and children?s health research that will reduce morbidity and mortality from conditions affecting women and children in developing countries. Obstetric patients with chronic hypertension, or preeclampsia in a prior pregnancy, presenting for care at or before 20 weeks of gestation will be randomized, in a masked, double-blinded fashion, to receive either Vitamin E (400 IU) and Vitamin C (1,000 mg) or placebo. The primary outcome assessed will be the incidence of preeclampsia. The Research Committee of the Department of Obstetrics and Gynecology, University of Sao Paulo, and the U.S. investigators will assess the long-term impact of this program on women?s and children?s health research, health care in Brazil, and international research collaboration.